The clinical and immunological responses following immunotherapy with bee venom and yellow jacket venom will be studied and correlated. The clinical results will be ascertained by the effects of inadvertant stings or planned stings under observation. Venom specific IgE and IgG will be measured in sequential serum samples. The effects of time and specific immunotherapy will be observed. Specific problems to be answered include mechanisms of insect sting allergy and immunity, the amount and duration of specific therapy and the natural history of insect sensitivity. Whole body insect extracts will be prepared by several methods. Skin test activity and immunotherapy responses will be compared to pure venom. Bee venom fractions in large quantity will be obtained for further analysis of their allergenic potency. In particular fraction I and hyaluronidase will be investigated. These fractions might also serve as future reference sources. Yellow jacket venom will also be fractionated and components analyzed for their allergenic and antigenic potency. Direct RAST and RAST inhibition tests will be used for standardization of venom, venom fractions and whole body extracts.